More room for mushrooms

Georgina Hill explains why there is more than meets the eye with this fungi

Tuesday 12 April 2016

The under appreciated fun-gi carries out a plethora of useful activities that can be investigated as possible eco-solutions. Searching the web for uses of mushrooms reveals mostly their amazing nutritional value, no doubt they are delicious, and use for their psychoactive properties. However, they have many more practical applications, too often overlooked.

Image: Aleksey Gnilenkov

Often illustrated as cute, white spotted red buttons, mushrooms have been seen in fairy tales and cartoons. Slightly less cute, polypore mushrooms produce woody fruiting bodies that were hollowed out and used by our ancestors to carry fire. The pit could stay illuminated for days allowing extended travel and foraging hours.

The same large, fibrous mushroom can be boiled and stretched to produce fabric. The stiff fabric can be used to make hats, furniture coverings and home accessories. The mass of interwoven filamentous hyphae, called the mycelium, has been used to make packaging rivalling ‘bad for the environment’, polystyrene. This foam can also be used for aquatic products and insulation. Importantly, the organic material can be biodecomposed resulting in close to zero residual waste.

Mushrooms are a key player in new bioremediation techniques, termed mycoremediation. Many microbes have been found that can digest large polymers, such as hydrocarbons from oil spills. Large oil spills gain international coverage in the press, however little is known about the thousands of gallons spilled every day on storage and transport. Emerging technologies are looking at bioremediation to combat global warming using methane digesting bacteria. As the microbial community is so large, with enough innovation and creativity, it seems we could use biological organisms to clean up pretty much any type of pollution.

Fungi are great decomposers, the mycelium secrete extracellular enzymes and acids that can break down organic pollutants. A limitation to fungal metabolism is the need for oxygen. However, fungi are important stimulators of microbial activity and plant growth in the dynamic soil environment. Combining remediation techniques to suit the particular environment and specific contaminant is important for effective clean up.

Fungi can be used in filtration techniques, termed microfiltration. There are extensive systems of contaminated ground water which threaten not only the environment but humans, as ground water is a major source of drinking water. It appears that a mushroom bed can decrease pollutant to nearly undetectable levels.

Interestingly, many mushroom species have been found to accumulate heavy metals. This detoxifies the environment allowing more microbial species to grow, thus enabling more contaminant removal. Mushrooms can then be harvest and the heavy metals recovered doubling benefits as the contaminated environment is cleaned and the recovered material could be sold and reused.

So let’s protect this underrated fun-gi. Unfortunately, due to deforestation, rising temperatures and imbalances in soil pH many, potentially useful species are becoming rare.